Thursday, July 16, 2009

The Eagle Has Landed

Forty years ago today, a three-hundred-sixty foot tall tower of aluminum rose slowly on a pillar of flame, arcing away from the coast of Florida across the Atlantic. At its top rode three men, beginning one of the greatest adventures in the history of mankind. They were riding the most powerful machine ever built by human hands, not on a mission of conquest, or of destruction, but of exploration and discovery. Over the next week or so, those of you who remember will probably take time to savor your own memories of those days. Me, I was an infant at the time. But nevertheless, I was born on one side of a historical chasm. For most of human history, our world had gotten steadily smaller. On that day in 1969, though, mankind's world became much larger.

But that's not really what I wanted to talk about today. Better writers than I will say these things, and probably say them better. Today, I wanted to talk about the also-rans. In the decades leading up to Apollo 11, there were a lot of different ideas thrown about as to how to get people up to the Moon, and bring them back again safely. Naturally, I probably won't be able to list them all, but I'll try to hit the high points.

Pride of place really has to go to Jules Verne. In his famous novel From the Earth to the Moon, Verne tries to write a serious story about a voyage to the Moon and back, based upon the best knowledge of the day. He dealt with the challenges and hazards the best he could, based upon the science known to him at the time. Sadly, it wouldn't have worked. A gun launcher big enough would have smashed its human passengers flat. But for inanimate cargo, a gun launcher might still become workable. Gerald Bull worked on the concept for years trying to find backers. Unfortunately, he chose poorly. Israel's Mossad took umbrage at his working for Saddam Hussein, and Bull contracted a fatal case of acute lead poisoning.

The next group of people to think about the problem seriously was the redoubtable British Interplanetary Society. They began to work on their design in 1937, publishing their results in July 1939. The only engines they had experience with were solid-fuel black powder rockets, so their design made use of those. It's an ... interesting approach. And it might even have worked. By clustering a whole bunch of solid rockets, and throwing them away as they burn out, they figured that they could achieve the velocity necessary. Sir Arthur Clarke worked on this project, so I have some confidence in the numbers. However, they got one thing dreadfully wrong. They assumed they'd need a heat shield on the way up, that they would discard after launch, but not on the way down. We know now that's totally backwards. So they'd have landed on the Moon just fine, but would have burnt to a crisp on the way back. Pity... But the parallel-cluster-staging idea they proposed didn't entirely die. The Russians used a variant of parallel staging on their R-7 rocket. And there was a private German attempt during the '70s, OTRAG, that used a very similar arrangement with liquid-fuel segments instead of solid. Near as I can tell, it ought to have worked. I expect that's why there was so much pressure on the German government to get it shut down.

The next serious design came after World War II, once German rocket expert Wernher von Braun relocated to the United States, and began working for the U.S. Army. Von Braun wrote a series of articles for Collier's in the 1950s, beautifully illustrated by Chesley Bonestell, describing the near-future exploits of man in space. Von Braun's moonship was gigantic, massing nearly 4,000 tons -- yes, that's right, 4,000 tons -- in low Earth orbit. The expedition would consist of three such ships, carrying a total of fifty men to explore Sinus Roris for six weeks. We who are children of the electronic and computer ages might well ask why the heck so many crew were necessary ... but you have to remember, back in those days, all electronics were vacuum-tube based, and things often broke. You had to carry along repair technicians. And you had to have three shifts of crew, since you had no automatics to watch over things while the crew slept. Also, no one knew if any man-made material could even withstand re-entry from Lunar distances ... so, the vehicle had to brake its way back into Earth orbit entirely on rocket thrust. Most of the ship's volume was taken up with fuel tankage. Needless to say, as splendid as the illustrations looked, this was a totally impractical plan. Ah well, back to the drawing board ...

Von Braun was nothing if not persistent. By the end of the '50s, he had another scheme hatched, and this time he had official Army backing. Project Horizon was intended to build a base upon the Moon capable of supporting 12 soldiers. The Horizon LERV lander was a much more realistic vehicle than his early '50s design. It still required fueling in-orbit, but no longer required assembly; the LERV was launched all in one piece by a Saturn II rocket. The lander was capable of carrying 10 to 16 men, and/or 22 tons of cargo. The plan was probably overly ambitious. The plan called for a 1965 landing, but most likely could not have landed any earlier than the 1970s, given the technical problems to overcome.

Naturally, this challenge was not going to go unanswered. The Space Race wasn't merely between the U.S. and the U.S.S.R., it was also between the sister services within the Department of Defense. There was a joke going around right after the launch of Sputnik. A junior Army officer ran up to a general and said breathlessly, "Sir! They've launched a satellite!" The general, startled, demanded "Who?" "It's the Russians," the junior officer replied. "Thank God," said the general, "for a moment, I was afraid it was the Navy." Both of the other major services were also getting into the game.

The Air Force's entry in the Moon derby was Project Lunex. Sometimes, I think this is the one we should have tried to do. But with the direct-ascent lander, and the lifting-body re-entry vehicle, it was probably a bridge too far, technically speaking. They also would have had a 12-man base as a goal, and thought they would be able to make a first landing in 1967. It's a fundamental law of engineering that everything costs more and takes longer, so I don't think they would have hit that goal. Early to mid 1970s would have been more like it. Still, that's a neat-looking lander.

The Navy also got into the lander business, albeit briefly. They never actually had any official plans for a base, but of all the military programs of the era, the Navy is the only group that got as far as building actual test hardware. The Navy SLV got as far as a test-stand prototype. But they got no farther. In 1961, the Kennedy administration cut all of these shenanigans short, and made the command decision that there would be one and only one American moon program, and that would be the Apollo program, run by NASA.

Which leads us to a partial answer for one of the perennial questions surrounding the Space Race: Why did Russia fall behind, when they had such a commanding lead in the early '60s? One answer is just this: they didn't have one Moon program. There were two or three going on simultaneously. Mostly, you had a bureaucratic knife-fight between two design bureau chiefs, both of whom wanted to be in charge: Sergei Korolev, and Vladimir Chelomei. If they had worked together they might well have beaten the Americans to the Moon, but they despised one another. A second problem, somewhat more serious, is that the Russians didn't get a firm go-ahead for lunar lander work until 1964 -- when the American design effort had been going full-blast for at least three years.

Korolev's first entry was a 1963 design he called L3. What happened to L1 and L2, we may never know. Korolev played his cards close to his vest, a habit learned the hard way via the Gulag. (This was another problem with the Soviet system, by the way; they had a penchant for wasting their best talent by throwing them in prison for stupid reasons.) This version never actually got official backing. Instead of making real progress on this design, Khruschev instead had him waste time on the Voskhod series, stunts of no real engineering value.

Meanwhile, Chelomei wasn't idle. He was pitching a different rocket and lander entirely, based upon his work for the military. is first design was the LK-3, based on his proposed UR-700 booster. With time, his design would mature to the somewhat more polished LK-700. Both were direct-ascent designs, which both suffer from the problem common with direct-ascent designs: you need a freaking ginormous rocket to lift it. Mind you, the UR-700 would have qualified, but it never got built.

But Korolev wasn't exaclty idle, either. Once Khruschev got sent to the knacker's yard in 1964, Korolev finally got a real go-ahead from the Soviet government. He had to return to the drawing board, and he had to come up with a plan that would work quickly. His final lander design was the LK, the closest thing the Soviet Union would ever have to the Apollo LM. But they started too late, and were never able to gain the resources to test things out properly. The N1 rocket Korolev needed for the mission never quite worked properly. Had he lived long enough, Korolev probably would have made it work; but he died in 1966. As it was, the N1's first stage was a plumber's nightmare, with thirty engines in the first stage alone. There were more powerful engines available, but they were designed by this chap named Chelomei, you see... The N1 was test-fired four times, none of them successfully.

For von Braun, though, the third time was the charm. With the creation of NASA in 1958, his Redstone team transferred to the new agency all at once. He brought his Saturn designs with him. The final evolution of that series was the mighty Saturn V, a towering beast taller than a football field is long, and as heavy as a World War II destroyer. On the morning of July 16, 1969, he watched from the firing room as his rocket rose into the Florida sky, bearing the astronauts Neil Armstrong, Buzz Aldrin, and Michael Collins on their rendezvous with destiny.

And our world would never again be the same.

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